http://www.ebay.com/itm/111008655809?redirect=mobile This company makes a plug for Glock grips that holds one round. Hey, never know when you might be one round short! $8.99 and free shipping Check his store for other calibers. Mine is for a Glock 20 and it fits perfectly. I am using it with gen 1 mags with plus 2 extensions. 1 in pipe, 16 in magazine, 2 in extension, and one in grip. Doing the math, my Glock 20, really is a 20! 20 rounds of 10mm is the way to go.